Hydraulic jack



Aug. 3l, 1937. G. A. couNTRYMAN *2,091,729

HYDRAULIC JACK l Filed Sept. 12, 1935 2 Sheets-Shut 1 Aug. 31, 1937.

G. A. couNTRYMAN HYDRAULIC JACK Filed sept. 12., 1935 l 2,0QL729 2 Sheets-Sheet 2 @95V Fig.

Patented Aug. 31', 1937 UNITED STATES I[PATENTl OFFICE 2,091,729 mmnAULrc J'Acx 'Guy A. Countryman, Ashland, Ohio Application September 12, 1935, Serial No. 40,295

9 claims. (c1. en -52) The invention relates to hydraulic jacks and more particularly to jacks of this type in which the pump is associated with the :lack as a unit.

Hydraulic jacks are used not only in an upright position vfor lifting purposes but in many cases are used in a horizontal or nearly horizontal position in connection with automobile body straightening and repairing tools and the like where it is often necessary to tilt the jack upon its longitudinal axis tol such a position that the pump andiluidfreservoir therefor are located below' the jack proper so that' oil will not feed from the reservoir to the pump.

Theobject of the present improvement is to provide a hydraulic jack so constructed that the fluid will feed from the reservoir to the pump regardless of whether the jack is in upright position or in any horizontal or substantially horizontal position.

A further object is to provide a hydraulic jack having a plurality of spaced communicating channels or passages between the iluid reservoir and pump with gravity arranged to automatically operate to admit fluid from the reservoirto the pump through the lowermost positioned passage or channel regardless of the position to which the jack may be turned upon its longitudinal axis.

The above objects' together withv others which will be apparent from the drawings and following description, 'or which may be later pointed out, may be attained by constructing the improved hydraulic jack in the manner illustrated in the accompanying drawings, in which Figure l is a lonigtudinal sectional view of a hydraulic jack embodying the invention;

Fig. 2, a. transverse detail section on the lines 2--2, Figs. 1 and 3;-

Fi'g. 3, a fragmentary 33, Fig. 2;

Fig, 4, a fragmentary 4 4, Fig. 2;

Fig. 5, a fragmentary detail section similar to Fig. 4, showing the other passage leading from the oil reservoir'to the check valves;

Fig. 6, a plan sectional view ofthe jack;

Fig. '1, a fragmentary transverse sectional view taken on the line Fig. 6;

Fig. 8, a fragmentary transverse sectional view taken on the line 8 8, Fig. 6; and Fig. 9, a fragmentary sectional view showing the connection of the fluid pipe from the pump to the upper end ofthe jack cylinder.

Similar numerals refer to similar parts throughout the drawings.

detail section on the line detail section on the line operated check valves thereiny The invention is applicable to any type of hydraulic jack, either single or double acting, but for the purpose of illustration the same is shown as applied to a double acting hydraulic'jack of the type disclosed in my prior Patent No. 5 1,985,151, granted December 18, i934.

The jack may be provided with a base in the form of a casing indicated generally at I0, of substantially oblong' shape and provided with the feet II and I2 at opposite ends for supporting the same upon the ground or floor in upright position when used'for lifting purposes or the may be provided with the depending internally threaded flange I1 mounted upon the threaded upper end of the cylinder, and a packing ring I3 of inverted substantially channel cross sectional shape may be located within the upwardly disposed annular ilange I9 of the head, said packing ring surrounding the ram or piston rod 20 and being held in place as by the screw ring 2l. lThe ram may have a shouldered portion 22 at its lower end portion, the extreme lower end of theram being reduced and threaded as shown atv 23 and having the piston 2d fixed thereon as by the nut 25 which clamps the two fiber or leather 30 washers 26 and the metal disk 2l therebetween.

A boss 29 may be formed upon the base at a point spaced from the annular flange I3, and is provided with an internally threaded socket 3U into which is screwed the lower end of the pump cylinder 3l. v

The pump is located within an oil reservoir including the shell 3 3 concentrically located with reference to. the pump cylinder and having its lower beveled end 3E received within the annularl 40 rib 35-formed upon the top of `the base, the inner side of said rib being preferably beveled as at 36 to receive the beveled lower end of the shell.

The head 3l of the reservoir has a central open- 45 ing 33 surrounding the pump cylinder 3l, and a depending peripheral flange 39 internally threaded for engagement with the threaded upper end of the shell 33, which together with the top wall is held clamped upon `thebase by means of the nut 40 mounted upon the threaded upper portion JI of the pump cylinder.

The pump plunger 42 is located within the cylinder 3| and provided with the ber or leather washer 43 at its lower end having the peripheral flange 44, the washer beingsecui'ed to the lower end of the plunger as by a screw 45.

A stufling box 46 may be provided at the upper 4end of the cylinder through which the plunger is the pump cylinder and leads to a horizontal passlidably received, a nut 41 being ilxed to the threaded upper end portion 48 of the plunger. The nut may be provided with ears 49 between which is received the handle lever 50 pivoted to the ears as by the pin 5|, the inner end of the lever being pivoted, as at 52, to the upper end of a link 53v pivoted at its lower end, as at 64, upon a lug 55 which may be formed upon the top wall 31 of the reservoir or upon any other suitable portion of apparatus.

A po'rt 56 communicates with the lower end lof sage 51 formed in the base casting and plugged at its outer end as by a screw 58, the other end thereof communicating with a vertical passage 59. A valve seat 6| is formed in the passage 59 to receive the gravity operated ball 62 which prevents oil from the pump from being forced back into the passage 59 but permits oil to be sucked up through the passage 59 into the pump.

A safety valve may be provided to prevent overloading of the jack and as shown, may include a tube 63, closed at its upper end as by the screw plug 64, the lower end of the tube communicating with the passage 59 above the ball 62.

A valve seat 65 is formed within the tube 63, the check ball valve 66 being normally yheld downward thereon as by the coil spring 61, the vtension on which may be adjusted bythe screw plug 64.

Transverse openings'68 in the tube 63 form a. communication between the interior of the tube above the valve seat 65, and the interior of the oil reservoir 33. With this construction, if a load greater than the capacity of the jack is placed upon the jack, the ball 66 will be raised by the oil pressure from the pump, permitting the oil to ow through the apertures 68 back into the reservoir, thus preventing undue straining of the jack.

A discharge passage 69 communicates with the lower end of the pump cylinder and leads downward through the base communicating with an intermediate portion of the transverse passage 10 which is closed at both ends.

As described in my prior Patent No. 1,985,151 above referred to, a valve seat 12 is provided in the passage 69 above the junction with the transverse passage 10 and a check ball valve 13 is normally held seated against the same so as to prevent oil from being sucked upward through the passage 69 into the pump but permitting oil to be forced downward from the pump through the passage 69 to the passage 10.

The longitudinally disposed passages 16 and 11 communicate with the transverse passage 10, these passages being each closed at one end and having valve seats 18 and 19 respectively at their open ends to receive the ball valves 80 andl 8| and also to hold the packing ring I8 under pressure.

A pair of screw plugs 90 and 9| are mounted in internally threaded openings axially located with reference to the passages 16 and 11 respectively, each of said screw plugs having a central bore 92 communicating with a plurality of radial passages 93, the outer ends of which communicate with an annular groove 94 in the peripheral portion of the screw plug, ports 95 and 96 forming communication between the grooves of the screw plugs 90 and 9| respectively and the oil reservoir 33.

The bore 92 of each of the screw plugs communicates with the corresponding transverse passage 83 or 84, the screw plugs being provided at .their ends with valve seats 91 and 98 respectively adapted to receive the ball valves 80 and 8| rethe seats 91 and 98 and toward the seats 18 andv 19. The stems 81 and 81a are preferably arranged to be simultaneously operated in reverse directions and this may be accomplished by means of gears xed upon the stems and meshing with each other. For the purpose of operating the stems, a handle may be provided upon one stem whereby rotation thereof, through the gears,x

will operate both stems in opposite directions.

All of the above described parts are disclosed in my prior patent above referred to and in themselves form no part of the present invention, being merely for the purpose of illustrating a complete hydraulic jack.

The invention pertains to means located in the intake to the pump from the reservoir and as shown, theintake passage 59 communicates at its lower end with a pair of voppositely disposed, outwardly and downwardly inclined passages |00 and |0 I, each of which is enlarged at its outer end as shown at I 02 and closed as by a. screw plug |03. /A valve seat |04 is formed in each of the enlarged portions of thesepassages, a check ball valve being located in the enlarged portion of each passage and arranged to cooperate with the corresponding valve seat |04.

As best shown in Fig. 2, the passages |00i-and |0| are located substantially at a 45? angle through the base and the enlarged portions of the passages |00 and |0| communicate with the upwardly inclined passages |06 and |01 respectively, leading to the lower end of the oil reservoir with which they communicate at opposite sides of the center thereof, the points of communication being oppositely offsetv from the center as shown in Fig. 2. I

In the operation of the jack, it should be noted that with the jackstanding in upright position,

both of the check balls |05 will be located at the outer ends of the enlarged portions |02 of the passages |00 and l0 and aI considerable distance away' from the valve seats |04. As the pump plunger is operated, on the upstroke oil is drawn from the reservoir through the passages |06 and |01 and then through the passages |00 and |0| upward through the passage 59 and then throughA the horizontal passages 51 to the intake passage 56, lling the pump cylinder.

On the ,downstroke of the pump plunger the ball 62 will be forced down upon the seat 6|, closing the passage 59, the oil being forced down horizontal position, one or the other of the intake passages |06 or |01 will be located below the oil level in the reservoir 33 soas to feed oil 10 from the reservoir to the pump, the other passage being automatically closed by means of the corresponding check ball |05. For instance, as shown in Fig. 2, the intake passage |06 would be located below the oil level in the reservoir while the passage |01, which may be located above the oil level, is cut olf from communication with the pump by means of the corresponding ball |05 seating against its valve seat |04, preventing the pump from sucking air from the reservoir through this passage.'

Thus, as the jack is rotated upon its horizontal axis to any desired or necessary position, the ball |05 of the lower most positioned passage |00 or |0| will by gravity fall away from its valve seat l while the ball controlling` the other passage will by gravity seat upon its valve seat, leaving the lowermost passage in communication with the pump and cutting off the uppermost passage from communication with the pump. Although the invention has been illustrated and described as applied to the particular type of double acting hydraulic jack illustrated in my prior APatent No. 1,985,151, it should be understood that the invention is equally well adapted to any form of hydraulic jack either single or double acting., it only being necessary that the series of passages and valves illustrated in Figs.

2, 3 and 4 be located between the intake port to the pump and the discharge from the oil reser- 4 40 Voir in the manner illustrated and described herein.

I claim: v

1. A hydraulic jack including a cylinder, a ram in thev cylinder, a pump, parallel to the jack cylinder, a passage forming communication between the pump and the cylinder, a fluid reservoir parallel to the pump, opposed, transversely disposed passages below the .fluid reservoir communicating with the pump at their inner endsV y and closed at their outer ends, said passages being located in a plane at an angle of substantially 45 to the plane in which the axes of the jack cylinder and fluid reservoir are located, gravity check balls in said passages, and passages communicating with intermediate portions of the last named passages and with the `iuid reservoir at opposite sides of the center thereof.

2. A hydraulic jack including a cylinder, a raml in the cylinder, a pump parallel to the jack cylinder, a passage forming communication between the pump and the cylinder, a fluidreservoir parallel to the pump, opposed, downwardly and outwardly inclined, transversely disposed `passages below the fluid reservoir communicating with the Dump at their inner ends and closed at their outer ends, said passages being located in a plane at an angle of substantially 45 to the plane in which the axes of the jack cylinder and uid reservoir are located, gravity check balls in said passages, and passages communicating with intermediate portions of the last named passages and with the fluid reservoir at opposite sides of the center thereof.

3. A hydraulicack including a cylinder, a ram in the cylinder, a pump parallel tothe jack cylinder, a passage forming communication between the pump and the cylinder, a` fluid reservoir parallel to the pump, opposed, angularly located, transversely disposed passages below the iiuid reservoir communicating with the pump at their inner ends and closed at their outer ends, said passages being located in a plane at an angle of substantiallly 45 to the plane in which the axes of the jack cylinder and fluid reservoir are located, gravity check balls in said passages, and passages communicating with intermediate ,por-

tions of the last named passages and with the 1 fluid reservoir at opposite sides of the center thereof.

4. A hydraulic jack including a cylinder, a ram in the cylinder, a pump parallel to the jack cylinder, a passage forming communication between the pump and the cylinder, a fluid reservoir parv check balls in said passages, and passages communicating with intermediate portions of the last named passages and with the fluid reservoir at opposite sides of the center thereof.

5. A hydraulic jack including a cylinder, a ram,

in the cylinder, a pump parallel to the jack4 cylinder, a passage forming communication between the pump and the cylinder, a fluid reservoir parallel to the pump, opposed, transversely disposed passages below the fluid reservoir .communicating with the pump at their inner ends` and closed at their outer ends, said passages being located in a plane at an angle of substantially 45 to the plane in whichthe axes of the jack cylinder and fluid reservoir are located, gravity check balls in said passages, and angularly inclined passages communicating with intermediate portions of the last named passages and withfthevfiuid reservoir at opposite sides of the center thereof.

6-44 hydraulic jack including a cylinder, a ram in the cylinder, a. pump parallel to the jack cylin der, va passage formingl communication between the pump and the cylinder, a iluid reservoir parallel to the pump, opposed, downwardly andoutwardly inclined, transversely disposed passages below the fluid reservoir communicating with the pump at their inner ends and closed at their outer l sages and with the uid reservoir at opposite sides of the center thereof.

'7. A hydraulic jack including a cylinder, a ram in the cylinder, a pump parallel to the jack cylinder, a passage forming communication between the pump and the cylinder, a fluid reservoir parallel to the pump, opposed, angularly'located,

transversely disposed passages below the fluid reservoir communicating with the pump at their inner ends and closed at their outer ends, said passages being located in a plane at an angle of substantially 45 to the plane in which the axes of the `jack cylinder and uid reservoir are located, gravity check ballsin said passages, and angularly inclined passages communicating with intermediate portions of the last named passages and with the uid reservoir at opposite sides of the center thereof.

8. A hydraulic jack including a cylinder, a ram in the cylinder, a pump parallel to the jack cylinder, a passage forming communication between the pump and the cylinder, a uid reservoir parallel to the pump, opposed, angularly located, downwardly and outwardly inclined, transversely disposed passages below the uid reservoir communicating with the pump at their inner ends and closed at their outer ends, said passages being located in a plane at an angle of substantially 45 to the plane in which the axes of the jack cylinder and uid reservoir are located, gravity check balls in said passages, and angularly inclined passages communicating with intermediate portions of the last named passages and with the fluid reservoir at opposite sides of the center thereof.

9. A hydraulic jack including a cylinder, a ram in the cylinder, a pump parallel to the jack cylinder, a passage forming communication between the pump and the cylinder, a uid reservoir parallel to the pump, opposed, transversely disposed passages below the fluid reservoir communicating with the pump at their inner endsl and closed at their outer ends, said passages being located in a plane at an angle of substantially 45 to the plane in which the axes of the rjack cylinder and fluid reservoir are located, gravity check balls in said passages, a check valve between said passages and the pump, and passages communicating with intermediate portions of the last named passages and with the uid reservoir at opposite sides ofthe center thereof.

GUY A. COUNTRYMAN. 

